25.02.2012 06:35, Atif Faheem wrote: > Hi. I have been experimenting with resource scalability in Pacemaker. I > started with no resources, and attempted to configure & start a few > hundred dummy resources (a dummy ocf script that does not load the CPU) > on a cluster of 4 virtual machines using crm configure, and noted that > after adding about 200 resources the cluster grinds to a halt. To start > an additional 100 resources, it took about 10 minutes for the crm > configure to complete, and an additional 10 minutes for the resources to > come up. I noted that the CIB process spikes to >90% as soon as a new > resource is configured on the system, and stays there for sometime. > During this time it is possible that "crm status" shows all nodes to be > offline. After a period of such instability, CIB CPU backs off, and then > the cluster is stable. Is this behavior expected with the > afore-mentioned cluster size / resource count? Are there any parameters > or knobs we may want to look at / twiddle? My understanding was that > with recent performance changes resource scaling should be much higher. >
Did you add/start resources one-by-one or in a batched mode? With "batched" I mean * dump configuration to file * change/add resource definitions in a file * upload new configuration to cluster with "crm configure load update" I now have cluster with ~300 resource instances (most of them are unallocated clone instances though, as a workaround to what has been hopefully fixed a day ago, cl#5038). And I never observe cib to be cpu-hog with batched approach (although that was a real problem with one-by-one resource handling). Best, Vladislav _______________________________________________ Pacemaker mailing list: Pacemaker@oss.clusterlabs.org http://oss.clusterlabs.org/mailman/listinfo/pacemaker Project Home: http://www.clusterlabs.org Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf Bugs: http://bugs.clusterlabs.org
